1. Field of the Invention
The present invention relates to a process for the utilization of refinery C4 streams containing iso and normal butanes and butenes. More particularly the invention relates to a process for producing alkylate feed from a mixed C4 stream. In one embodiment the invention relates to a process which produces isooctane in addition to alkylate feed.
2. Related Information
Refinery C4 streams have recently been utilized in the production of methyl tertiary butyl ether (MTBE) for use as an oxygenate additive and octane improver in motor gasolines. Processes and catalyst systems for their use in this manner have been developed over the years and include U.S. Pat. Nos. 4,215,011; 4,242,530; 4,232,177; 4,307,254; 4,336,407; 4,375,576 and like patents.
Refinery C4 streams have also been used as the source of butenes and isobutane for feed to cold acid alkylation processes which produce isooctane. Generally there has been an imbalance in the amount of isobutene and butenes in refinery C4 streams which have led to the use of the MTBE processes which utilize the isobutene, effectively removing it from the C4 stream.
Environmental concerns have led at least the state of California to ban the use of MTBE in gasoline. Other processes for the balancing of the iso/normal butenes are now required.